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			          Sea cucumber - Wikipedia, the free encyclopedia
			           
 Sea cucumbers are echinoderms from the class Holothuroidea. They are marine animals with a leathery skin and an elongated body containing a single, branched gonad. https://en.wikipedia.org/wiki/Sea_cucumber
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			          Sea Cucumber - Echinoderm - Britannica
			           
 Sea cucumber (class Holothuroidea), any of 1,200 species of marine invertebrates that constitute a class within the phylum Echinodermata. http://www.britannica.com/animal/sea-cucumber
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			          Sea Cucumber Facts - Encyclopedia
			           
 sea cucumber  any of the flexible, elongated echinoderms belonging to the class Holothuroidea. http://www.encyclopedia.com/topic/sea_cucumber.aspx
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			          Sea Cucumber - HowStuffWorks
			           
 The sea cucumber is an echinoderm shaped like a cucumber or sausage, related to the starfish and the sea urchin. Learn more about the sea cucumber. http://animals.howstuffworks.com/marine-life
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			          Sea Cucumber Pictures and Facts - National Geographic
			           
 Learn all you wanted to know about sea cucumbers with pictures, videos, photos, facts, and news from National Geographic. http://animals.nationalgeographic.com/animals/invertebrates/sea-cucumber
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			          Johnson's Sea Cucumber - Parastichopus johnsoni - Monterey Bay Aquarium
			           
 Sea cucumbers are soft-bodied and live at all ocean depths, from the shallows to the abyss. http://www.montereybayaquarium.org/animal-guide/invertebrates/johnsons-sea-cucumber
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			          Sea Cucumber Facts and Information
			           
 Some live on the ocean floor and others a planktonic, meaning that they float in the ocean with the currents. https://www.nwf.org/Wildlife/Wildlife-Library/Invertebrates/Sea-Cucumber.aspx
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			          Sea Cucumber Facts for Kids
			           
 Sea cucumbers belong to the group of animals called echinoderms. Their closest relatives are starfish and sea urchins. http://www.softschools.com/facts/animals/sea_cucumber_facts/478
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			          Elasipodida - Wikipedia, the free encyclopedia
			           
 Elasipodida is an order of sea cucumbers. They are somewhat unusual in appearance, in comparison with other sea cucumbers, having numerous appendages, including conical papillae and leaf-like tentacles. https://en.wikipedia.org/wiki/Elasipodida
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			          Dendrochirotida - Wikipedia, the free encyclopedia
			           
 ndrochirotida are an order of sea cucumbers. Members of this order have branched tentacles and are suspension feeders. Examples include Thyonella and Cucumaria. https://en.wikipedia.org/wiki/Dendrochirotida
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			          Aspidochirotida - Wikipedia, the free encyclopedia
			           
 They are distinguished from other sea cucumbers by the presence of flattened, often leaf-like tentacles, but without the other large appendages found in the related order Elasipodida. https://en.wikipedia.org/wiki/Aspidochirotida
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			          Apodida - Wikipedia, the free encyclopedia
			           
 The Apodida is an order of littoral to deep-sea, largely infaunal holothurians. This order comprises three families, 32 genera and about 270 known species, called apodids. https://en.wikipedia.org/wiki/Apodida
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			          Pelagothuria natatrix - Wikipedia, the free encyclopedia
			           
 Pelagothuria natatrix is a species of sea cucumber, in the family Pelagothuriidae. It may be the strangest species of its kind, as it looks like a jellyfish and is the only pelagic echinoderm known to date. https://en.wikipedia.org/wiki/Pelagothuria_natatrix